staging: lustre: lmv: Match MDT where the FID locates first

With DNE every object can have two locks in different namespaces:
lookup lock in space of MDT storing direntry and update/open lock
in space of MDT storing inode. In lmv_find_cbdata/lmv_lock_lock,
it should try the MDT that the FID maps to first, since this can
be easily found, and only try others if that fails.

In the error handler of lmv_add_targets, it should check whether
ld_tgt_count is being increased before ld_tgt_count is being -1.

Signed-off-by: wang di <di.wang@intel.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4098
Reviewed-on: http://review.whamcloud.com/8019
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Fan Yong <fan.yong@intel.com>
Signed-off-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/lustre/lustre/lmv/lmv_internal.h b/drivers/staging/lustre/lustre/lmv/lmv_internal.h
index dbd1da6a51de4f7c70cc64bcef9c49762c29bfb6..faf6a7ba86377da0b12fdd09b0acdc2c44d76040 100644 (file)
--- a/drivers/staging/lustre/lustre/lmv/lmv_internal.h
+++ b/drivers/staging/lustre/lustre/lmv/lmv_internal.h
@@ -64,35 +64,56 @@ int lmv_revalidate_slaves(struct obd_export *exp, struct mdt_body *mbody,
                          int extra_lock_flags);
 
 static inline struct lmv_tgt_desc *
-lmv_get_target(struct lmv_obd *lmv, u32 mds)
+lmv_get_target(struct lmv_obd *lmv, u32 mdt_idx, int *index)
 {
-       int count = lmv->desc.ld_tgt_count;
        int i;
 
-       for (i = 0; i < count; i++) {
+       for (i = 0; i < lmv->desc.ld_tgt_count; i++) {
                if (!lmv->tgts[i])
                        continue;
 
-               if (lmv->tgts[i]->ltd_idx == mds)
+               if (lmv->tgts[i]->ltd_idx == mdt_idx) {
+                       if (index)
+                               *index = i;
                        return lmv->tgts[i];
+               }
        }
 
        return ERR_PTR(-ENODEV);
 }
 
-static inline struct lmv_tgt_desc *
-lmv_find_target(struct lmv_obd *lmv, const struct lu_fid *fid)
+static inline int
+lmv_find_target_index(struct lmv_obd *lmv, const struct lu_fid *fid)
 {
-       u32 mds = 0;
-       int rc;
+       struct lmv_tgt_desc *ltd;
+       u32 mdt_idx = 0;
+       int index = 0;
 
        if (lmv->desc.ld_tgt_count > 1) {
-               rc = lmv_fld_lookup(lmv, fid, &mds);
-               if (rc)
-                       return ERR_PTR(rc);
+               int rc;
+
+               rc = lmv_fld_lookup(lmv, fid, &mdt_idx);
+               if (rc < 0)
+                       return rc;
        }
 
-       return lmv_get_target(lmv, mds);
+       ltd = lmv_get_target(lmv, mdt_idx, &index);
+       if (IS_ERR(ltd))
+               return PTR_ERR(ltd);
+
+       return index;
+}
+
+static inline struct lmv_tgt_desc *
+lmv_find_target(struct lmv_obd *lmv, const struct lu_fid *fid)
+{
+       int index;
+
+       index = lmv_find_target_index(lmv, fid);
+       if (index < 0)
+               return ERR_PTR(index);
+
+       return lmv->tgts[index];
 }
 
 static inline int lmv_stripe_md_size(int stripe_count)

diff --git a/drivers/staging/lustre/lustre/lmv/lmv_obd.c b/drivers/staging/lustre/lustre/lmv/lmv_obd.c
index 9821f69bc03efe4b25c5e50821429119863457e2..6917a034ca279dfb7be3ef8bae5ae4e6d17cdbb8 100644 (file)
--- a/drivers/staging/lustre/lustre/lmv/lmv_obd.c
+++ b/drivers/staging/lustre/lustre/lmv/lmv_obd.c
@@ -480,6 +480,7 @@ static int lmv_add_target(struct obd_device *obd, struct obd_uuid *uuidp,
 {
        struct lmv_obd      *lmv = &obd->u.lmv;
        struct lmv_tgt_desc *tgt;
+       int orig_tgt_count = 0;
        int               rc = 0;
 
        CDEBUG(D_CONFIG, "Target uuid: %s. index %d\n", uuidp->uuid, index);
@@ -549,14 +550,17 @@ static int lmv_add_target(struct obd_device *obd, struct obd_uuid *uuidp,
        tgt->ltd_uuid = *uuidp;
        tgt->ltd_active = 0;
        lmv->tgts[index] = tgt;
-       if (index >= lmv->desc.ld_tgt_count)
+       if (index >= lmv->desc.ld_tgt_count) {
+               orig_tgt_count = lmv->desc.ld_tgt_count;
                lmv->desc.ld_tgt_count = index + 1;
+       }
 
        if (lmv->connected) {
                rc = lmv_connect_mdc(obd, tgt);
                if (rc) {
                        spin_lock(&lmv->lmv_lock);
-                       lmv->desc.ld_tgt_count--;
+                       if (lmv->desc.ld_tgt_count == index + 1)
+                               lmv->desc.ld_tgt_count = orig_tgt_count;
                        memset(tgt, 0, sizeof(*tgt));
                        spin_unlock(&lmv->lmv_lock);
                } else {
@@ -1263,7 +1267,7 @@ int __lmv_fid_alloc(struct lmv_obd *lmv, struct lu_fid *fid, u32 mds)
        struct lmv_tgt_desc     *tgt;
        int                      rc;
 
-       tgt = lmv_get_target(lmv, mds);
+       tgt = lmv_get_target(lmv, mds, NULL);
        if (IS_ERR(tgt))
                return PTR_ERR(tgt);
 
@@ -1610,6 +1614,7 @@ static int lmv_find_cbdata(struct obd_export *exp, const struct lu_fid *fid,
 {
        struct obd_device   *obd = exp->exp_obd;
        struct lmv_obd      *lmv = &obd->u.lmv;
+       int tgt;
        int               i;
        int               rc;
 
@@ -1622,12 +1627,22 @@ static int lmv_find_cbdata(struct obd_export *exp, const struct lu_fid *fid,
        /*
         * With DNE every object can have two locks in different namespaces:
         * lookup lock in space of MDT storing direntry and update/open lock in
-        * space of MDT storing inode.
+        * space of MDT storing inode. Try the MDT that the FID maps to first,
+        * since this can be easily found, and only try others if that fails.
         */
-       for (i = 0; i < lmv->desc.ld_tgt_count; i++) {
-               if (!lmv->tgts[i] || !lmv->tgts[i]->ltd_exp)
+       for (i = 0, tgt = lmv_find_target_index(lmv, fid);
+            i < lmv->desc.ld_tgt_count;
+            i++, tgt = (tgt + 1) % lmv->desc.ld_tgt_count) {
+               if (tgt < 0) {
+                       CDEBUG(D_HA, "%s: "DFID" is inaccessible: rc = %d\n",
+                              obd->obd_name, PFID(fid), tgt);
+                       tgt = 0;
+               }
+
+               if (!lmv->tgts[tgt] || !lmv->tgts[tgt]->ltd_exp)
                        continue;
-               rc = md_find_cbdata(lmv->tgts[i]->ltd_exp, fid, it, data);
+
+               rc = md_find_cbdata(lmv->tgts[tgt]->ltd_exp, fid, it, data);
                if (rc)
                        return rc;
        }
@@ -1676,7 +1691,7 @@ lmv_locate_target_for_name(struct lmv_obd *lmv, struct lmv_stripe_md *lsm,
 
        *fid = oinfo->lmo_fid;
        *mds = oinfo->lmo_mds;
-       tgt = lmv_get_target(lmv, *mds);
+       tgt = lmv_get_target(lmv, *mds, NULL);
 
        CDEBUG(D_INFO, "locate on mds %u "DFID"\n", *mds, PFID(fid));
        return tgt;
@@ -2866,24 +2881,32 @@ static enum ldlm_mode lmv_lock_match(struct obd_export *exp, __u64 flags,
        struct obd_device       *obd = exp->exp_obd;
        struct lmv_obd    *lmv = &obd->u.lmv;
        enum ldlm_mode        rc;
+       int tgt;
        int                   i;
 
        CDEBUG(D_INODE, "Lock match for "DFID"\n", PFID(fid));
 
        /*
-        * With CMD every object can have two locks in different namespaces:
-        * lookup lock in space of mds storing direntry and update/open lock in
-        * space of mds storing inode. Thus we check all targets, not only that
-        * one fid was created in.
+        * With DNE every object can have two locks in different namespaces:
+        * lookup lock in space of MDT storing direntry and update/open lock in
+        * space of MDT storing inode.  Try the MDT that the FID maps to first,
+        * since this can be easily found, and only try others if that fails.
         */
-       for (i = 0; i < lmv->desc.ld_tgt_count; i++) {
-               struct lmv_tgt_desc *tgt = lmv->tgts[i];
+       for (i = 0, tgt = lmv_find_target_index(lmv, fid);
+            i < lmv->desc.ld_tgt_count;
+            i++, tgt = (tgt + 1) % lmv->desc.ld_tgt_count) {
+               if (tgt < 0) {
+                       CDEBUG(D_HA, "%s: "DFID" is inaccessible: rc = %d\n",
+                              obd->obd_name, PFID(fid), tgt);
+                       tgt = 0;
+               }
 
-               if (!tgt || !tgt->ltd_exp || !tgt->ltd_active)
+               if (!lmv->tgts[tgt] || !lmv->tgts[tgt]->ltd_exp ||
+                   !lmv->tgts[tgt]->ltd_active)
                        continue;
 
-               rc = md_lock_match(tgt->ltd_exp, flags, fid, type, policy, mode,
-                                  lockh);
+               rc = md_lock_match(lmv->tgts[tgt]->ltd_exp, flags, fid,
+                                  type, policy, mode, lockh);
                if (rc)
                        return rc;
        }